Treatment of metastatic breast cancer with 𝑛𝑎𝑏-paclitaxel in the community practice setting: a US Oncology survey.

Background: Different dosages-schedules of nab-paclitaxel have been assessed in trials of metastatic breast cancer (MBC). However, there is limited information on nab-paclitaxel dosing-scheduling in the community setting.

Objective: To report on experience with nab-paclitaxel for human epidermal growth factor receptor 2 (HER2)-negative MBC and identify patient characteristics affecting nab-paclitaxel treatment patterns in the community practice setting.

Methods: From September 6-October 21, 2013, a 35-question, web-based survey on nab-paclitaxel dosing, toxicities leading to dose modifications, management, and treatment duration was sent to US Oncology network oncologists. Respondents were categorized by percentage of their patients with HER2-negative MBC who received nab-paclitaxel.

Results: 104 of 428 oncologists responded; 84% were from large practices (≥16 oncologists), and 56% had a high level of experience using nab-paclitaxel. For first- and second-line treatment, 100 mg/m² weekly was the most common starting dosage-schedule, followed by 125 mg/m² weekly and 260 mg/m² every 3 weeks (q3w); 150 mg/m² weekly was used least frequently. Several factors, including select aggressive disease characteristics, were found to affect nab-paclitaxel dose selection. Weekly dosing was preferred in patients with select aggressive disease characteristics, whereas q3w dosing was commonly used in patients aged ≤50 years and those with good performance status. Differences in management styles among oncologists with high compared with infrequent nab-paclitaxel experience were also observed. Peripheral neuropathy and neutropenia were common dose-limiting toxicities.

Limitations: Recall and response bias may be limitations of this study.

Conclusions: In the community setting, nab-paclitaxel 100 mg/m² weekly was the most commonly used starting dose for patients with HER2-negative MBC, including those with aggressive disease characteristics.